Electjig rubnace



Feb. 16 1926. v

E. L. SMALLEY v ELECTRIC FURNACE. ori ihal Filed August a, 1920 2Sheets-Shut 1 INVENTOR [flW/A L. 5/ 7/4445) 6% A TTORNEV fRe. 16,269

Feb. 16 lags: I

5. L. SMALLEY- 2130mm Fmimcs 2 Sheets-Shed 4 2.

fori inu Filed Au ust a. 1920 Reissuecl Feb. 16, 1926.

UNITED STATES PATENT OFFICE.

EDWIN L. SMALLEY, OF MILWAUKEE, WISCONSIN, ASSIGNOR T ELECTRIC HEATINGAPPARATUS COMPANY, OF NEWARK, NEW- JERSEY.

ELECTRIC FURNACE.

Original No. 1,459,801, dated June 26 1923, Serial No. 401,717, filedAugust 6, 1920.

reissue filed June 22, 1925. Serial No. 38,927.

To (221 whom, it may concern: Be it known that I, EDWIN L. SMALLEY, a

citizen of the United States, and a resident of Milwaukee, in the countyof Milwaukee and State. of Wisconsin, have invented certain new anduseful Improvements in Electrio Furnaces, of which the follow ng is aspecification.

This invention relates to electric furnaces, and my improvement isdirected to certain novel means of supporting and engaging the heatingelements thereof against the interior surfaces of such furnaces.

Particularly in the instance of a furnace vhaving a housing composed ofbricks of pressed infusoria-l earth, or of other suitable material whichis a non-conductor of electricity, my invention comprehendsthe integralformation .with said bricks, at their surface exposed to the furnace,interior, of reception means for the resistance conductors constitutingthe heating units. and with said reception means I provide locking meansto retain the heating units in such engagement and positively hold themcompactcd snugly against the interior surfaces of the furnace.

As an example of my invention I form upon the housing bricks, at theirsurfaces which are to be exposed to the furnace in terior, a seriesofprojections. or bosses, arranged in spaced relation, and in separatedgroups and tiers of groups, so that parallel strands of a resistor, maybe lodged between adjacent projections or bosses, and pins of porcelainor other suitable material which 1s a non-conductor of electricity arethen entered within aligned holes that extend through each series ofsaid projections or bosses, beyond the lodged resistor strands, toprevent extrusion thereof.

Other features and advantages of my in vention will hereinafter appear.

' In the drawings I v Figure 1' is a front sectional elevation of afurnace equipped with my improved resistor lodgement and securing means.

Fig. 2 is an enlarged, detail side view in section of the resistorlodgement and securing means.

Fig. 3 is a front view thereof, reduced, and

Fig. 4 is a detail of a modification.

In the example of an electrical furnace Application for I illustrated inFig. 1, it is seen to include the housing brick 1, whose surface isexposed to the furnace interior.

Usuallv the heating elements, as resistance conductors in the form ofcoils of return bend or other character, have been carried byunitrefractories or plates with which the interior surface of thefurnace is lined, but with the aid of my present in) .provement I amable to dispense with all such lining plates. Instead I provide thehousing brick itself with projections or bosses 2, arranged in groups,and directed towards the furnace interior. The projections orbosses ineach group are spaced apart sufiic'iently for the lodgement, betweenadjacent projections or bosses, of a resistor strand, and if theresistor is of the return bend type, having parallel strands 3. as hereshown, then the interspaces separating the projections or bosses in agroup will coincide'with the spaced arrangement of the strands, and thuswill receire said strands. which are thereby respectively supported andinsulated one from another.

The groups of projections or bosses 2 are only arbitrarily indicated inthe drawing as each including six projections or bosses for thecontainment of a return bend coil having that number of strands, butobviously said number may be varied. As rep resented in Fig. 3, a numberof groups. 1, of said projections or bosses are provided, in lateralspaced arrangement, with their respective projections or bosses andinter spaces aligned, so that a lateral series oi said groups willunitedly support all the strands of a complete return bend coil tendiherethrough in parallelism with the housing surface, spaced therefromsuiiiciently to clear the contained resistor strands, and a pin or thelike 7 of porcelain or other suitable material that is a nonconductor ofelectricity, is removably entered in said aligned orifices,to thuscomprise a guard or lock to retain the resistor or heating element inits lodged position.

'Said pin 7 is shown as having a head 8 to 1 serve asa stop in coactionwith the uppermost projection or boss, and to permit its withdrawal forthe removal of the resistor.

\Vhen there is more than one tier of .groups t in a single plane,the'groups of adjacent tiers are disposed in staggered relation, as perthe example in Fig. 3, where two of such tiersare shown, because by thismeans the pin 7 in a lower tier are thereby rendered capable ofwithdrawal through'the spaces separating adjacent groups of an uppertier.

In Fig. 1 the sur-faces 'of the side Walls of the furnace housing areshown as provided with exposed heating elements, lodged and locked inposition in the manner described, and the same is alsotrue of the upperand lower surfaces of the housing interior, excepting that the heatingelement in the bottom surface, with its lodging and retaining means,may, when desirable, be

covered by a refractory plate, as indicated at 9 in said figure. V

It should also be noted that in the cases where more than one tier ofgroups are employed, in he staggered relation referred to, the adjacentrejections or bosses of succeding tiers provide between them thelodgenient spaces for a final strand in a resistor 3 element.

It will be appreciated that the herein described means ofsecuringresistance condoctors in exposed relation against the surface ofthe housing brick, early heating effect is provided, and also thecontingency of broken unit refractories, thus needing replacement, iseliminated.

The projections or bosses provided upon the surface of the housing brickmay be formed integrally therewith, but may iiistead be in theform ofseparate members, having suitable means of engagement with the housing.Thus, in Fig. 4, I have shown suppor ing means 10 like thoseemployod in.my atent No...1,3'-l 6,854. Plates, as 11,

are carried by support 10, said plates having the projections or bosses12, which receive between them the resistors 13, and pins it are enteredthrough orifices provided therefor in said projections or bosses, toretain the resistors in their lodged position.

Variations within the spirit and scope of my invention are equallycomprehended herein by virtue of the foregoing disclosure.

1. An electric furnace comprising-a suppoitof refractory material, apreformed return-bend resistor element disposed upon said support inexposed relation to the interior space of the furnace, and refractoryspecified.

port of refractory material, a preformed return-bend resistor elementassociated there with in exposed relation to the interior space of thefurnace, and spaced elongated refractory members carried by saidsupport, and extending transversely of the strands of said resistorelement over Opposite poi- .tions thereof whereby to retain the same in.

position with respectto said support; said refractory members andsaid-resistor ele ment being arranged to permit of the ready removal ofsaid resistor element; substantialyas specified.

3. An electric furnace comprising a support having channels formedthereon, a resistor element disposed in said channels, and adapted to bereadily removed therefrom, and a plurality of retaining means arrangedin spaced relation on said sup--.

port, and adapted to engageopposite end" portions of said resistorelement to retain the sauna" in said channels; said. retaining means andsaid resistor clement being'arranged to permit of the ready removal ofsaid element, substantially as specified.

4. An electric furnace comprising a support having channels formedthereon, a 1 6: sistor element disposed in said channels, and membersextending trans mrsely of said channels at opposite ends thereof andadapted to engage opposite portions of said 1-0-- sistor elementtoretain the same in said channels; said retaining members and saidresistor element being arranged to permit of the ready remo val of-saidresistor eiement from said channels, substantially as 5. An electricfurnace comprising a refractory snpporha preformed return-bond resistorelement disposed upon said sup port, and a plurality of retaining' meansarranged in spaced relation on said support, and extending transverselyof the strands of said resistor element .in engagement with oppositeportions thereof to retain the same in position incloso proximity tosaid support; said retaining means serving to permit of' the readyremoval of said resistor element, substantially as specified.

6. An electric furnace comprising a wall of refractory material, apreformed returnbend resistor element associated therewith and exposedto the interior space of. the furnace, retaining members carried bysaidv wall and adapted to engage said resistor element to retain thesame in position with re spect to said wall, and means interposedbetween successive strands of said element said projecting -.saidheating element being readi to maintain said strands in spaced relation,substantially as specified.

' 7. An electric furnace comprisin a Wall of refractory material, apreforme returnbend resistor element disposed relatively to said wall inexposed relation to the interior space of the furnace, refractorymembers carried by said wall and adapte to engage said. element toretain the same in operativeposition relatively to said wall and toperniit of the ready removal of said element, and means interposedbetween successive strands of said element to maintainsaid strands inspaced relation, substantially 'as specified 8. An electric furnacecomprising a support of refractory material, a pluralit of spacedrefractory members projecting rom said support, a preformed return-bendresistor element disposed upon said support with 'the strands thereofreceived between refractory members, and refractory members carried bysaid support,

and. adapted to' engage said resistor element 1 for retaining the samein' position in close proximity to said support, and serving to permitof the ready removal of said element, substantially as specified.

9. In an electric furnace, in combination,

a refractory.support, a group of members projecting from said support, areturn bend heating 0 cment disposed upon said support with the strandsthereof received between said projecting members; said projectingmembers being spacedto ermit of y moved relative to said projectingmembers and from said support, and a plurality of spaced retaining meanscarried by said support and extending over and adapted to engageopposite portions of said heating eleinent, and serving to retain thesame in positiou with said strands disposed between said projectingmembers and to permit of the removal of said heating element frombetween said projecting members, substantially as specified.

10. In an'electric furnace, tion, a support, a plurality of spacedmember bond "heating element disposed upon said support with the strandsthereof received between sa'idpro-jectingmembers, and members reinovablyengaging said projecting members. and extending across said heatingelement to retain the same in position on said support, substantially asspecified.

11. lnhan electric furnace, in COlflb'lllfl: tioufa refractory support,a plurality of spaced refractory members projecting from said support, areturn-bend heating thereof disposed between said projectingtowardslaterally se arated groups of s aced'bosses in combiuaojectingfrom said support,a return-. of spaced bosses upon said housingsurface,

element day of June, 1925. disposed. upon said support with the strandsp refractory members, and refractory members extending transversely ofsaid strands and removably disposed within said projecting refractorymembers .for retaining said heating element on said support in exposedrelation to the interior 0 said furnace, substantially as specified. i

a 12. An electric furnace engageable with the housing for the remov-'able lodgement. of an inwardly, uncovered tion, a housing whose innersurfaceis eX- posed to the furnace interior,

heating element having parallel group of spaced bosses 11 surface,whereof adjacent lodgement spectively, and removable means to securesaid strands .in their lodgement.

14. In an electric furnace, in combinastrands, a on said housing osses'permit the tion, a housing whose inner surface is ex-' v having itshousing exposed to the furnace interior, means.

a returnbend between them of said strands reose'd to the furnaceinterior, a return-bend 1 eating element having parallel strands, agroup of spaced bosses upon said housing surface, whereof adjacentbosses permit the lodgeinent between them of said strands, 'respectivelsaid bosses having aligned orifices, an a pin of non-conductive materialremovably entered in said orifices to retain said strands in theirlodged position.

.15'.I n an electric furnace, in combination, a housing whose innersurface is posed to the furnace interior, a return bend resistanceconductor having parallelstrands,

upon said ousing surface, ad acent bosses in each group being aligned toafford lodgement between them for a'conductor strand in exposedrelation, and removable securing means for said strand 16. In anelectric furnace, in combination,,a housing whose inner surface isexposed to the furnace interior, return bend resistance conductorshaving parallel strands, tiers of laterally separated groups Signed atPittsburgh in the county of Allegheny and State of Penns., this 18th'EDVVIN L. SMALLEY.

